Another separatist leader, Shabir Shah, has been arrested in Indian-administered Kashmir as part of efforts to stop anti-India protests.
A six-day old curfew has been strictly enforced in Muslim-majority areas, preventing traditional large gatherings at mosques for Friday prayers.
The protests began in June in a dispute over the transfer of land to a trust in charge of an important Hindu shrine.
They escalated into some of Kashmir's biggest separatist protests in years.
Shabir Shah had been in hiding for more than a week, the BBC's Altaf Hussain reports from Kashmir's summer capital, Srinagar.
He was arrested in an area close to the city. He has spent some 20 years in prison for his separatist activities.
Earlier this week the police arrested four other prominent separatist leaders, Syed Ali Shah Geelani, Mirwaiz Omar Farooq, Yasin Malik and Asiya Andrabi.
Ms Andrabi has been charged under the Public Safety Act which allows for detention without trial for up to two years.
Our correspondent says Ms Andrabi played a crucial role in forging unity among separatist groups in Kashmir.